/Engine/Source/Runtime/Core/Public/Misc/ExpressionParserTypes.h
Generate a token for the specified number of chars, at the current read position (or end of Accumulate)
[TOptional](API\Runtime\Core\IO\TOptional)< [FStringToken](API\Runtime\Core\Misc\FStringToken) > GenerateToken ( int32 NumChars, [FStringToken](API\Runtime\Core\Misc\FStringToken) * Accumulate ) const